“To tear oneself from beloved haunts to incur the fatigues and perils of a long journey is undoubtedly a painful decision; yet the bird courageously submits to the inevitable, but in the hope of coming back again some day. The strong reassuring the weak, the older ones guiding the young, the departing flock forms itself into a caravan and takes wing for the south. The sea is crossed, the treacherous sea from which, at long intervals, rises an island as halting-place. Many perish in the crossing, many reach the goal worn with hunger and spent with fatigue. “The day for starting on this momentous journey is decided upon in a great assembly, toward the end of August for the window-swallow, and considerably later, even as late as November, for the chimney-swallow. When once the date has been fixed, the window-swallows gather together daily for several days on the roofs of tall buildings. Every few minutes small parties detach themselves from the general conclave and circle about in the air with anxious cries, taking a parting look at their native haunts, and paying them a last farewell. Then they return to their places among their companions and join in noisy chatter on the subject of their hopes and fears, all the while preparing themselves for the distant expedition by a careful inspection of their plumage and a final touch to one lustrous feather after another. “After several repetitions of these farewells a plaintive twittering announces the fateful hour. The moment has come, it is time to start. The flock rises, the emigrants are off for the south. If one of them has been marked with a red string around the claw in order to be recognized, you may be sure you will see it come back the next spring and take possession of its nest again with little cries of joy at finding it intact and ready for occupancy after a few repairs. “With their vigorous wings the duck and goose, in their wild state, are ardent travelers. On a gray day in November, when there are signs of snow, it is not unusual to see passing from north to south, at a great height, birds arranged in single file, or in a double file meeting in a point, like the two branches of the letter V. These birds are a flock of either ducks or geese in the act of migrating. “If the flock is of no great size, the birds composing it arrange themselves in one continuous file, the beak of each following bird touching the tail of the preceding, in order that the passage opened through the air may not have time to close again. But if the flock is a large one, two files of equal length are formed, which meet at an acute angle, the front of the moving mass.